In this paper, isobutane (R-600a) is used as a suitable substitute for (R-134a) when changing the length of capillary tube. And the experimental data on capillary tube are obtained under different conditions such as (subcooling and ambient temperatures) on domestic refrigerator (9ft3 size), this data shows that (R-600a) a suitable substitute for (R134a) .The test presented a model for a steady state, two-phase flow in capillary tube for vapour compression system .The numerical model depends on conservation equations (mass, energy and momentum) as wall as the equation of state for refrigerant. The solution methodology was implemented by using finite difference techniques. The system results indicate that it is possible to change the refri
... Show MoreThe research aimed to compare the performance of the commercial and the Islamic banks listed in the Palestinian's Stock Exchange .To achieve the objectives of the study we selected all the commercial and the Islamic banks listed in the Palestinian Stock Exchange to obtain the necessary data for the analysis process during the period of (2009-2013) .the comparison based on the performance indicators ( liquidity rate, profitability rate ,the activity rate and the market rate).
a statistical method was used to analyze the date to find the performance differences between the commercial banks,
... Show MoreThe vortex rate sensor is a fluidic gyroscope with no moving parts and can be used in very difficult
conditions like radiation, high temperature and noise with minimum cost of manufacturing and
maintenance. A vortex rate sensor made of wood has been designed and manufactured to study
theoretically and experimentally its static performance .A rig has been built to carry out the study,
the test carried out with three different air flow rates (100, 150, and 200 l/min).The results show that
the relation between the differential pressure taken from the sensor pickoff points and the angular
velocity of the sensor was linear.The present work involved theoretical and experimental study of
vortex rate sensor static characteri
This study focuses on the behavior of simply supported perforated prestressed concrete rafters (PPCRs) under single midspan monotonic static loading. The experimental program consisted of testing seven specimens; one solid (control) rafter, and six perforated with quadrilateral openings. The main investigated variables are the number and height of the openings. The test findings indicate that, in comparison to the solid rafter, the presence of quadrilateral openings in the PPCRs led to reducing the load capacity by (4.3-36%) and increase the midspan deflection at ultimate by (14.8-33%). Also, increasing the number of concrete posts between openings resulted in increasing the failure load and decreasing the deflection at all stages o
... Show MoreThe vortex rate sensor is a fluidic gyroscope with no moving parts and can be used in very difficult conditions like radiation, high temperature and noise with minimum cost of manufacturing and maintenance. A vortex rate sensor made of wood has been designed and manufactured to study theoretically and experimentally its static performance .A rig has been built to carry out the study,
the test carried out with three different air flow rates (100, 150, and 200 l/min).The results show that the relation between the differential pressure taken from the sensor pickoff points and the angular velocity of the sensor was linear.The present work involved theoretical and experimental study of vortex rate sensor static characteristics .Vortex rat
Visible-light photodetectors constructed Fe2O3 were manufactured effectively concluded chemical precipitation technique, films deposited on glass substrate and Si wafer below diverse dopant (0,2,4,6)% of Cl, enhancement in intensity with X-ray diffraction analysis was showed through favored orientation along the (110) plane, the optical measurement presented direct allowed with reduced band gap energies thru variation doping ratio , current–voltage characteristics Fe2O3 /p-Si heterojunction revealed respectable correcting performance in dark, amplified by way of intensity of incident light, moreover good photodetector properties with enhancement in responsivity occurred at wavelength between 400 nm and 470 nm.
The esterification of oleic acid with 2-ethylhexanol in presence of sulfuric acid as homogeneous catalyst was investigated in this work to produce 2-ethylhexyl oleate (biodiesel) by using semi batch reactive distillation. The effect of reaction temperature (100 to 130°C), 2-ethylhexanol:oleic acid molar ratio (1:1 to 1:3) and catalysts concentration (0.2 to 1wt%) were studied. Higher conversion of 97% was achieved with operating conditions of reaction temperature of 130°C, molar ratio of free fatty acid to alcohol of 1:2 and catalyst concentration of 1wt%. A simulation was adopted from basic principles of the reactive distillation using MATLAB to describe the process. Good agreement was achieved.
This study was conducted at the poultry research station to the office of Agricultural Research / Ministry of Agriculture / during the period 4/1/2016 to 5/5/2016 and 336 one-day-old Ross308 chicks were used, and fed on diets provided with dried dill (Anethum gravelens) at levels 0.4, 0.6 and 0.8% for treatments D2, D3 and D4, respectively, and they were compared with the control treatment D1. Each treatment included three replicates in each replicate contain 28 birds, in order to study the effect of adding different levels of dried dill plant on the productive performance and some characteristics of the carcass for broilers. The results showed a significant increase (p<0.05) in the average body weight at 5 weeks of age for the treatments (
... Show More— In light of the pandemic that has swept the world, the use of e-learning in educational institutions has become an urgent necessity for continued knowledge communication with students. Educational institutions can benefit from the free tools that Google provide and from these applications, Google classroom which is characterized by ease of use, but the efficiency of using Google classroom is affected by several variables not studied in previous studies Clearly, this study aimed to identify the use of Google classroom as a system for managing e-learning and the factors affecting the performance of students and lecturer. The data of this study were collected from 219 members of the faculty and students at the College of Administra
... Show MoreIn light of the increasing importance of interim financial statements they provided these lists of information that enables users of accounting information to make wise investment decisions and predict the company's activities in light of changes the updated rather than wait until the end of the year and accessing information provided by the annual financial statements. In light of this research has come to the most important set of conclusions the adoption of interim financial information has been audited by the external auditor to the availability of basic qualitative characteristics in the accounting information contained in the (appropriate and timely manner, reliability and comparability) and this in turn leads to the impact on reli
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